Timeout.prototype.ref - Node documentation
method Timeout.prototype.ref

Usage in Deno

import { Timeout } from "node:timers";
Timeout.prototype.ref(): this

When called, requests that the Node.js event loop not exit so long as theTimeout is active. Calling timeout.ref() multiple times will have no effect.

By default, all Timeout objects are "ref'ed", making it normally unnecessary to call timeout.ref() unless timeout.unref() had been called previously.

Return Type

this

a reference to timeout